Ginseng is one of the most important medicinal herbs taking deep root in Korean daily life in such a degree that Korea is called as suzerain state of ginseng. Ginseng has been regarded as miraculous panacea in the Chinese medical field through all ages. The effects of ginseng have been recognized all over the world, including the China at early times and Europe and America recently. Finally, ginseng has taken a position as the trademark of Korea.
Although modern medical science is developed to the highest degree nowadays, internal treatment often depends on the Chinese medical science, and thus ginseng is increasingly on demand. Additionally, intensive research and development into ginseng, particularly into its essential components and effects are made by western medical scientists due to the specific functions of ginseng. Therefore, Korean-made ginseng and ginseng products become matters of interest.
Ginseng may be classified into three types, i.e., fresh ginseng maintaining its original shape, red ginseng and white ginseng, depending on kinds of processing methods. Fresh ginseng, which is non-processed ginseng harvested in the field, contains about 75% of water, and thus may be easily decomposed and damaged during a process of circulation. Therefore, it is difficult to store fresh ginseng for a long time without using any special storage equipments or packages.
Generally, red ginseng is obtained by steaming fresh ginseng still having its shell, followed by drying. Red ginseng shows a light yellowish brown color or light reddish brown color. On the contrary, white ginseng is obtained by drying fresh ginseng, whose shell is removed or not, by sunlight, hot air, etc., in a non-boiled or non-steamed state. White ginseng has water content of about 13% and shows a milky white color or light yellow color. Additionally, white ginseng may be classified into unbent ginseng, semi-bent ginseng and bent ginseng, depending on shapes after drying.
Because ginseng having a great amount of vegetable fibers is not susceptible to grinding power compared to hard and brittle materials, it is difficult to prepare micropowder of ginseng in an industrial scale. Although several small-sized corporations are present in Korea for processing ginseng roots by a mechanical method to obtain ginseng powder, most of them depends on cutter mill, roll crusher and pin mill processes, thereby providing crude ground powder having an average particle diameter of about 150 μm. Therefore, most of the powder products are merely used in lower value-added applications, for example ginseng powder products or materials for ginseng cookies. Up to date, intensive research and development into methods for preparing high-quality ginseng powder have not been made.
Ginseng micropowder having an average particle diameter of 10 μm or less shows excellent dispersibility, miscibility and absorptiveness. Accordingly, such micropowder can be used in higher value-added applications, for example various health-aid foods or medicines such as drinks, tablets or capsules and cosmetic products such as functional skin care agents or skin packs. However, there is no epochal method for preparing ginseng micropowder via mechanical grinding.
Because ginseng contains a large amount of vegetable fibers and has a low hardness, there is a limitation in reducing the particle diameter of ginseng powder by merely applying grinding power to ginseng with a grinder. Moreover, according to such simple grinding methods, powder having a non-uniform particle size is obtained. Additionally, active components of ginseng may be degenerated or contaminated by the friction between ginseng and a grinder.